/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: AliceMana
 * Date: 2022-08-07
 * Time: 19:25
 */
public class Test2 {
    public static void main(String[] args) {
        A1 a1 = new A1();
        A1 a2 = new B1();
        A1 a3 = new C1();
    }
}
class A1 {

}
class B1 extends A1 {

}
class C1 extends B1{

}
